Spark intensifier for spark plugs



July Z0, 1954 J. A. H. cAsToNGAY 2,684,451

SPARK INTENSIFIER FOR SPARK PLUGS Filed Sept. 2l, 1950 Nulla',

F/G. a F/e. /0

The three spark intensiers shown in Fig. l are each as a whole indicatedat 8, and the construction thereof is the same as is shown in Figs. 2and 3, to which I will now refer.

What I term the bulb or body member of the spark intensifier isrepresented at il. It is desirably formed of some suitable translucentplastic insulating material, preferably clear Lucte, which is shown asprovided with a window or opening ld extending, this embodiment of theinvention, all the way through the bulb or body member 9 and providingair circulation, thereby preventing corrosion. The opening i@ may be ofany suitable diameter and form, and may be beveled or flaring at itsends, as indicated at il. The opening is large enough for the insertionof a gauge, as will be explained. The opening lil is preferably circularin cross section. Each bulb or body member preferably of a circular formin cross section, but not necessarily so. At the top and at the bottom,it is provided with a threaded opening i2, i3, respectively, and thereinare received the threaded extensions lil, l5 of lengthwise-adjustable,tubular or cup-like meinbers IE5, l?, the former of which receives thewire cable end lil and the latter of which is vertically slotted toprovide two springy members or parts which snap into the spark plugsocket member 3.

rThe distance apart of the extreme ends of the extensions Ed., I5, andhence the extent of the spark gap, is very accurately established byproviding a short, narrow strip or gauge of metal of `just the rightthickness, and inserting horizontally one end of it well into the windowIl) and then scewing inward by the thumb and nngers one or both of themembers i6, il until their inner ends ld, l both touch the upper andlower faces respectively cf the properly inserted metal piece or gauge.

In Fig. fl the spark plug as a whole is indicated at I8, it having athreaded lower end I8. The upper end of it is provided with a threadedextension i9. The bulb or body member is indicated at 20. It ispreferably of molded plastic, translucent material, such clear Lucite,and it is shown as having a through-hole 2i like that shown in Fig. 2,preferably circular in diameter, but of any desired shape and for thesame purpose. In the upper and lower faces of the bulb or body member 2dare threaded holes such as shown in Fig. 2, the lower end receiving thethreaded extension is and the upper one receiving the threaded end 22 ofthe metal end 23 receiving the wire cable and threaded about the lowerend of which is a nut 24.

The construction shown in Figs 5 and 6 is for attachment to the screwtype of spark plug as in Fig. 4, it differs from that shown in Fig. 4only in the bulb or body member 25 has a window 26 which extends onlyhalfway through the same, that is, to the threaded ends i9 and 22, andbeing of any suitable diameter.

The construction shown in Figs. 7 and 8 is the same as shown in Figs.4., 5 and 6, excepting that the bulb or body member il has no opening orwindow, because it is molded with the adjustment taken care of inmolding.

The construction shown in Figs. 9, l0 and l1 is one in which the bulb orbody member 2S is of plastic, translucent material, preferably Lucite,that is molded about the set-screw end part 29 and the internallythreaded part 3Q. There is provided a through-opening Si, here shown asof rectangular form in cross section. The part 29 may have a nut 32which is molded into the bulb or body member 23. It may be hexagonal orof other form. In this form there is preferably the usual adjustmentprovided for the parts 29 and 3i) in the bulb or body member 28.

In the construction shown in Fig. 12 the bulb or body member 32, also oftranslucent plastic material, preferably Lucite, is provided with athrough-window 33, and preferably molded into said bulb or body member32 is a tube 3d having a spur 35 at the lower end to make most effectivecontact with the wires of the cable end that is to be received in theopen-ended tube 34. There is molded into the opposite end of the bulb orbody member 52 a slotted end 36 to be snapped onto the spark plug.

The construction shown in Fig. 13 diers from what is shown in thepreceding ngures, in that the bulb or body member 3l is positioneddirectly in the wire cable itself, the two parts of which are shown at38. 3S. In this construction the bulb or body member 3l' is providedwith a through-opening or window iii of any suitable diamete-. two parteof the cable 33, are respectively provided with threaded metallic endslll, i2 threaded into threaded holes in the bulb or body member, as inFigs. 2 and 4., for example, so that the spark gap may be accuratelyadjusted or established, as has already been explained in connectionwith Figs. 2 and li.

The construction shown in Fig. le differs from what is shown in all theother figures, in that the bulb or body member which, as in the otherfigures, is of translucent plastic material, preferably Lucite, has twothreaded openings in the top and bottom respectively thereof, the topopening receiving therein the threaded screw lli having a head l5 andthe lower opening receiving a short threaded piece l into the lowerexposed end whereof is received the internally threaded socket member ilitself may receive a wire cable end, not shown. The bulb or body member(i3 a through-window or opening i8 and the screw head i5 is received ashort link i9 which at its other end is provided with an opening 5d bywhich the link may be readily secured to any spark plug or any desiredpart of the mechanism.

In Fig. l5 I have shown in longitudinal centrai section a form ofinvention which is the same in all respects as that shown in Fig. 2 andtherefore bearing the same reference numerals as in 2 but with a primeadded excepting that the member il is provided with a set screw 5! andthe member I is provided with an adjusting screw 52. Both of thesescrews may be turned by a screw so that their inner ends may be broughtinto contact with an inserted gauge, alreacy explained in connectionwith other figures.

In the construction shown in Figs. 5 to i0, the body member is shown asrectangular in cross section, but it may be circular. In all the formsthe shape of the body member may be varied as desired.

In all the embodiments the adjustable elements may be adjusted byscrew-driver inserted in the transverse slot in the end thereof.

When the spark intensifier is mounted on top of the spark plug, and inthose cases where a window is provided, I desir-ably cover the window bysome suitable adhesive material as, for example, Scotch tape.

I preferably do not provide the window, al-

though my invention includes the provision thereof, as shown in manyfigures of the drawing, and for that reason the construction shown inFig. 7 and also that shown in Fig. 16 represent the preferableconstructions.

The construction shown in Fig. 16 in side elevation is substantially thesame as that shown in section in Fig. 7, and the same reference numeralsare provided with a prime to indicate the same parts. The differencebetween the two constructions shown in Figs. 7 and 16 respectively isthat in Fig. 7 the spark intensiiier is secured by screw l directly uponthe spark plug indicated at it, whereas in Fig. 16 I provide a sleeveextension as in Fig. 2 at I 'I and in Fig. 12 at 39 which is slottedalong diametrically opposite lines, so that it may be fitted onto thespark plug.

So far as I am aware, Lucite has never been used for my purpose. 1 havetested many materials and find that Lucite is best adapted for mypurpose. Particularly because it can be very readily and successfullymachined as by providing sharply defined screw threads in the wallthereof, so as to receive threaded electrodes. I am aware that Bakeliteand porcelain have been proposed, but neither of these is transparent.Although Bakelite may be termed translucent in Very thin layers, it isnot so satisfactory for applicants purpose as Lucite, and certainly isnot so nearly transparent. I am also aware that glass has -beenproposed. While this is transparent, it is not adapted to be readily andsuccessfully machined as by providing well-delined screw threads toreceive the threaded electrodes.

As stated, the distributor head or cup is preferably constructed ofplastic material. Preferably it is made completely of clear Lucite, andpreferably embodies the spark intensier integral therewith, or the sparkintensier construction may be removably and adjustably attached thereto.

This intensifier principle, as herein disclosed, may also apply directlyto a spark plug. The intensifier may be molded over the upper spark plugportion, having in such case a spark gap head instead of a screw head.

Having thus described several embodiments of the invention, it is to beunderstood that although specii'ic terms are employed, they are used ina generic and descriptive sense and not for purposes of limitation, thescope of the invention being set forth in the following claims.

I claim:

1. A spark intensifier for spark plugs of automobile and other internalcombustion engines, comprising a complete, one-piece body member ofreadily machined clear Lucite material that is transparent so that thespark lighL may be clearly seen, said body member being axially internally machine screw threaded, screws threaded respectively anddirectly into said threads in the body member and extendinglongitudinally axially therefrom, and having their inner` endsadjustably spaced apart from each other merely suiioiently to provide aspark tubes of conducting material, having closed inner ends and thereabutting directly and respectively against the end walls of said bodymember and held directly upon said screws respectively, each oi saidtubes having an open outer end to receive detachably an element of theignition system, at least one of said tubes being longitudinally slottedproviding two springy parts to be snapped into circumferential grippingengagement with a spark plug member or the like.

2. A spark intensifier for spark plugs of automobile and other internalcombustion engines, in accordance with claim 1, wherein said body memberhas a transversely extending window opening to the spark gap for aircirculation.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,205,682 Sutherlin Nov. 21, 1916 1,240,721 Hultgreen Sept.18, 1917 1,278,441 Cunningham Sept. l0, 1918 1,388,348 Koehler Aug. 23,1921 1,413,140 Sutherlin Apr. 18, 1922 1,699,829 Bartley Jan. 22, 19291,700,211 Anderson J an. 29, 1929 1,798,789 Gale Mar. 31, 1931 1,898,204Hibbs Jan. 3, 1933 1,962,949 Claybrook June 12, 1934

